202 W. ARCHER. 



origin to one side at some distance down from the apex ; the 

 body is thus bilaterally symmetrical; that aspect whence the 

 pseudopodial stem springs the author would speak of as its 

 "dorsal" and the opposite as its "ventral" aspect. The 

 " oral" aperture is likeAvise somewhat below the apex and to 

 one side of the principal axis, hence, seen in " side view," 

 this form shows there a somewhat deep inlet or sinus in 

 which lies the pseudopodial stem between the body and the 

 test. (See lower part of fig. 3.) The reddish or colourless 

 contents are described by the author as if in constant rota- 

 tion ; his examples contained several non-contractile vacu- 

 oles and sundry incepted objects. 



The only mode of increase observed by the author con- 

 sisted in division. The first indication of this (as he describes) 

 was, the appearance of a new pseudopodial-stem at the base 

 of the example and the perforation of the test at this place. At 

 the same time the test along with the contents becomes more 

 and more deeply constricted, the isthmus thus being formed 

 becomes more and more drawn out, until it at last gives way. 

 The two new "tailed" examples gradually draw in these 

 appendages. 



Of this curious form the author saw no mode of encysting 

 indicated, though such of course is to be expected. 



The author does not say if there were any appearance after 

 the " drawing in " of the " tails," of the filling up of the 

 aperture in the test. May one here venture on the sugges- 

 tion that this is really not a form appertaining to Gromia at 

 all, but a true amphistomatous rhizopod, and that the fresh 

 perforation and emission of a new " pseudopodial stem " as 

 described by the author is really not founded on fact, but that 

 the perforation was there always, although in the examples 

 studied by him there were at the time — possibly until the con- 

 striction had begun to be formed — no pseudopodia issuing 

 therefrom ? This indeed in the first-known amphistomatous 

 form, Amphitrema Wrightianum, is occasionally to be seen, 

 that is, a tuft of pseudopodia may be evident only from one 

 extremity, and indeed in almost every case the pseudopodial 

 stem is more strongly pronounced, and the tuft of pseudo- 

 podia is notably more copiously given oflf, from one of the 

 apices than from the other. At the same time most of the 

 author's figures show a necklike prolongation only at one 

 end, but see his fig. 45 (I.e.), where an example is shown 

 during constriction, and with a well-developed "neck" and 

 pronounced " oral " aperture at both extremities. 



If that were so, that is, that Cienkowski's G. paludosa 

 were really an amphistomatous form, the supposition might 



